Direct objects are the nouns or pronouns that receive the action of a transitive verb. A transitive verb is a verb that requires a direct object to complete its meaning.
Examples of sentences without direct objects:
* The sun shines brightly. (The verb "shines" is intransitive, meaning it doesn't take a direct object.)
* The cat sleeps peacefully. (The verb "sleeps" is intransitive.)
* We walked to the park. (The verb "walked" is intransitive.)
Examples of sentences with direct objects:
* The dog chased the ball. ("Ball" is the direct object of the verb "chased".)
* She wrote a letter. ("Letter" is the direct object of the verb "wrote".)
* They ate pizza. ("Pizza" is the direct object of the verb "ate".)
In summary, not all sentences require direct objects. The presence or absence of a direct object depends on whether the verb is transitive or intransitive.